Insulating fabric.



G. H. ELLIS.

INSULATING FABRIC.

APPLICATION FILED MAR.19,1910.

Patented Aug. 25, 1914 WITNESJEJ //vv NTOR 56 5y #5 ATTORNEXS Avg m UNITED STATES PATENT OFFICE.

GEORGE H. ELLIS, OF ST. PAUL,

MINNESOTA, ASSIGNO-R,

BY MESNE ASSIGNMENTS, TO

NORTHERN INSULATING COMPANY, OF ST. PAUL, MINNESOTA, A CORPORATION OF Specification of Letters Patent.

INSULATING FABRIC.

Patented Aug. 25, 1914:.

To all whom it may concern Be it known that I, GEORGE H. ELLIS, a citizen of the United States, residing at St. Paul, in the county of Ramsey and State of Minnesota, have invented certain new and useful Improvements in Insulating Fabric; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention has for its object to provide, as a new article of manufacture or product, a felted or matted fibrous insulating fabric.

The present improved product is in the nature of an improvement on the product disclosed and broadly claimed in Patent No. 908,681, issued of date January 5, 1909, to James E. Lappen, and entitled Flax felt. In the said prior Lap en patent, the socalled flax felt is made rom long fibers that are intertangled and matted together, so that they constitute a porous, coherent and selfsustaining body having considerable tensile strength. This is also true of the present improved product. Also, in common with the material defined in the said patent, the from which the body of the fabric is made, is degummed or partly degummed, so as to separate the shive from the fiber;.and a part, usually about fifty per cent, more or less, of the shive or woody substance, is commingled with the fiber. This use of the shive renders the felted material more porous than it would be if entirely freed from shive and, furthermore, greatly reduces the cost of the manufactured material.

The present improved product difi'ers from the product of the said patent chiefly in the following important features: The cordices or fibrous bundles of the flax or similar fibrous material are not only partially separated as in the product of the said prior patent, but are shredded or frayed so that they are formed with beard or fuzz which very closely unite and very thoroughly intertangle and form, in the insulating material, a very strong mechanical binder made up of fluffy and very soft and light body portions which also serve to very greatly increase the heat insulating capacity of the completed fabric or felted material.

The invention is illustrated in the accompanying drawing which represents more or portion plete process, by means of which proved insulating fabric may be commerless diagrammatically a cross section of a of the improved product.

In the drawing, the cordices or fibrous bundles hereinbefore referred to are indicated by the heavy black lines and are designated by the numeral 1. The beard or fuzz formed upon the fibers 1 is indicated at 2, the strands of which intertangle with each other and with adjacent fibers, as shown in the drawing.

Actual practice has demonstrated that my improved lnsulating fabric or felted board of a given thickness will have higher heat insulating efiiciency, will be lighter in weight and yet much tougher and coherent or self-sustaining in its nature than a felted board or material of the same thickness made as described in the said prior Lappen Patent. 908,681. The shredded or frayed heard or fuzz of the fiber so thoroughly intertangle that they bind together not only themselves but the coarser fibers and the shive and, hence, their high efficiency as a mechanical binder. The lightness, of the material is due to the fluffy nature of a large part of the material which is made up of the intertangled fuzz or beard; and the increased insulating efiiciency seems to be due largely to the greatly increased number of very small air cells produced in the material by the said inter-tangled fuzz or beard. To produce this shredding onfraying of the fibrous stock with the resulting beard or fuzz thereon, and to remove the pectose or gum, at least in part,- from the stock, the fibrous stock is subjected to a carding action under water, this action being a feature which is disclosed and broadly claimed in my companion application Serial No. 550,860 filed of even date herewith and entitled Process of producing insulating fabric. In fact, my said process application discloses a comthis imcially made. In my prior Patent, No. 1,022,778 of April 9, 1912, I have disclosed an apparatus which is adapted for use to commercially and economically carry out the improved process of making my improved insulating fabric.

What I claim is:

1. An insulating fabric composed of shredded and fibrous stock felted together the fibers being provided with a beard or fuzz, said beard or fuzz being intertangled and matted to provide a reinforcement in addition to that resulting from the felting of the fibers.

2. An insulating fabric composed of long partly degummed fiber and shive or Woody particles, the said fibrous portions being shredded or frayed and formed with a beard or fuzz intertangled and matted together to provide a reinforcement in addition to the reinforcement resulting from the felting.

3. An insulating fabric composed of shredded and fibrous stock felted together the fibers being provided With a beard or fuzz, the beard or fuzz on each fiber being intertangled both with the beard or fuzz on adjacent fibers and with the adjacent fibers themselves, thereby providing a reinforcement in addition to that resulting from the felting of the fibers.

In testlmony whereof I aflix my signature 1n presence of tWo Witnesses.

GEORGE H. ELLIS.

Witnesses .ALIOE V. SWANSON, HARRY D. KILGORE. 

